EP2159684B1 - Playback of streamed media - Google Patents
Playback of streamed media Download PDFInfo
- Publication number
- EP2159684B1 EP2159684B1 EP09166588.5A EP09166588A EP2159684B1 EP 2159684 B1 EP2159684 B1 EP 2159684B1 EP 09166588 A EP09166588 A EP 09166588A EP 2159684 B1 EP2159684 B1 EP 2159684B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- decoder
- buffering
- decoder buffer
- client device
- server
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/80—Responding to QoS
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L49/00—Packet switching elements
- H04L49/90—Buffering arrangements
- H04L49/9005—Buffering arrangements using dynamic buffer space allocation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L49/00—Packet switching elements
- H04L49/90—Buffering arrangements
- H04L49/9023—Buffering arrangements for implementing a jitter-buffer
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/1066—Session management
- H04L65/1101—Session protocols
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/40—Support for services or applications
- H04L65/403—Arrangements for multi-party communication, e.g. for conferences
- H04L65/4038—Arrangements for multi-party communication, e.g. for conferences with floor control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/61—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio
- H04L65/612—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio for unicast
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/75—Media network packet handling
- H04L65/752—Media network packet handling adapting media to network capabilities
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/75—Media network packet handling
- H04L65/762—Media network packet handling at the source
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/75—Media network packet handling
- H04L65/764—Media network packet handling at the destination
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/234—Processing of video elementary streams, e.g. splicing of video streams, manipulating MPEG-4 scene graphs
- H04N21/23406—Processing of video elementary streams, e.g. splicing of video streams, manipulating MPEG-4 scene graphs involving management of server-side video buffer
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream, rendering scenes according to MPEG-4 scene graphs
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream, rendering scenes according to MPEG-4 scene graphs
- H04N21/44004—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream, rendering scenes according to MPEG-4 scene graphs involving video buffer management, e.g. video decoder buffer or video display buffer
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client
- H04N21/65—Transmission of management data between client and server
- H04N21/658—Transmission by the client directed to the server
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client
- H04N21/65—Transmission of management data between client and server
- H04N21/658—Transmission by the client directed to the server
- H04N21/6582—Data stored in the client, e.g. viewing habits, hardware capabilities, credit card number
Definitions
- the present invention relates generally to the streaming of media over packet-based networks. More specifically, the invention relates a buffering mechanism for improving playback of the streamed media from packet delay variation due to encoding and packetisation.
- a multimedia terminal In conversational packet-switched multimedia systems, e.g., in IP-based video conferencing systems, different types of media are normally carried in separate packets. Moreover, packets are typically carried on top of a best-effort network protocol that cannot guarantee a constant transmission delay, but rather the delay may vary from packet to packet. Consequently, packets having the same presentation (playback) time-stamp may not be received at the same time, and the reception interval of two packets may not be the same as their presentation interval (in terms of time). Thus, in order to maintain playback synchronization between different media types and to maintain the correct playback rate, a multimedia terminal typically buffers received data for a short period (e.g. less than half a second) in order to smooth out delay variation. Herein, this type of buffer is referred to as a delay jitter buffer. In conversational packet-switched multimedia systems buffering can take place before and / or after media data decoding.
- Delay jitter buffering is also applied in streaming systems. Due to the fact that streaming is a non-conversational application, the delay jitter buffer required may be considerably larger than in conversational applications.
- the server When a streaming player has established a connection to a server and requested a multimedia stream to be downloaded, the server begins to transmit the desired stream. The player typically does not start playing the stream back immediately, but rather it buffers the incoming data for a certain period, typically a few seconds.
- this type of buffering is referred to as initial buffering. Initial buffering provides the ability to smooth out transmission delay variations in a manner similar to that provided by delay jitter buffering in conversational applications.
- PDUs lost protocol data units
- Buffering allows the player to decode and play data from the buffer while allowing the possibility for lost PDUs to be retransmitted. If the buffering period is sufficiently long the retransmitted PDUs are received in time to be decoded and played at the scheduled moment.
- Initial buffering in streaming clients provides a further advantage that cannot be achieved in conversational systems: it allows the data rate of the media transmitted from the server to vary. In other words, media packets can be temporarily transmitted faster or slower than their playback rate, as long as the receiver buffer does not overflow or underflow.
- the fluctuation in the data rate may originate from two sources. The first source of fluctuation is due to the fact that the compression efficiency achievable in some media types, such as video, depends on the contents of the source data. Consequently, if a stable quality is desired, the bit-rate of the resulting compressed bit-stream varies. Typically, a stable audio-visual quality is subjectively more pleasing than a varying quality.
- initial buffering enables a more pleasing audio-visual quality to be achieved compared with a system without initial buffering, such as a video conferencing system.
- video encoding standards define at least two types of frame.
- the principal frame types are INTRA or I-frames and INTER or P-frames.
- An INTRA frame is encoded on the basis of information contained within the image itself, while a P-frame is encoded with reference to at least one other frame, usually a frame occurring earlier in the video sequence. Due to the significant temporal redundancy between successive frames of a digital video sequence, it is possible to encode an INTER frame with a significantly smaller amount of data than that required to represent an INTRA frame. Thus, INTRA frames are used comparatively infrequently in an encoded video sequence.
- an encoded sequence starts with an INTRA frame (as there is no previous frame available to be used as a reference in the construction of an INTER frame).
- INTRA frames may be inserted into the sequence periodically e.g. at regular intervals, in order to compensate for errors that may accumulate and propagate through a succession of predicted (INTER) frames.
- INTRA frames are also commonly used at scene cuts where the image content of consecutive frames changes so much that predictive coding does not provide effective data reduction.
- a typical encoded video stream generally starts with an INTRA coded frame and comprises a sequence of INTER frames interspersed with occasional INTRA frames, the amount of data required to represent an INTRA frame being several (e.g. 5 - 10) times greater than that required to represent an INTER coded frame.
- the amount of data required to represent each INTER frame also varies according to the level of similarity / difference with its reference frame and the amount of detail in the image.
- a second source of fluctuation occurs when packet losses in fixed IP networks occur in bursts.
- well-designed streaming servers schedule the transmission of packets carefully and packets may not be sent precisely at the rate they are played back at the receiving end.
- network servers are implemented in such a way that they try to achieve a constant rate of packet transmission.
- a server may also adjust the rate of packet transmission in accordance with prevailing network conditions, reducing the packet transmission rate when the network becomes congested and increasing it if network conditions allow, for example. This typically occurs by adjusting the advertised window of the acknowledgement message sent in TCP (transmission control protocol).
- TCP transmission control protocol
- client terminal refers to any end-user electronic device such as handheld devices (PDAs), wireless terminals, as well as desktop and laptop computers and set top boxes.
- This variation in delay, which arises due to encoding, packetisation and packet transmission from a server can be termed an “encoding” or “server-specific” variation delay. It is independent of, or in addition to, delay jitter that arises due to variations in transmission time within the network.
- initial buffering enables the accommodation of fluctuations in transmitted data rate from the aforementioned disadvantages i.e. encoding or server-specific delay variation and network transmission related delay variation. Initial buffering helps to provide a more stable audio-visual quality and to avoid network congestion and packet losses.
- Initial buffering may also be performed after decoding of the received media data. This has the disadvantage that the dimensions of the buffer must be relatively large, as the buffering is performed on decoded data. The combined effect of encoding, server-specific and network transmission delay variations also tends to increase the initial buffering requirement.
- the encoding of media data and the way in which encoded data is encapsulated into packets and transmitted from a server causes a decoder in a receiving client terminal to experience a variable delay in receiving the information it requires to reconstruct the media data, even if the transmission delay through the network is constant.
- a post-decoder buffer does not provide a means of absorbing this form of delay variation prior to decoding.
- a method of streaming media data by transmitting a plurality of data packets over a network from a source server to a client device wherein the client device includes a decoder for decoding encoded packets.
- the method is characterised in that the client device further includes a pre-decoder buffer having a variable initial buffering time and a variable buffer size established for receiving the transmitted data from the source server prior to decoding in the decoder, and wherein the variable initial buffering time and variable buffer size of the pre-decoder buffer are dynamically adapted for improved playback performance by the client device.
- a system for streaming media data by transmitting a plurality of data packets including a source server hosting the media data, a network serving as a transmission medium for the data packets; and a client device capable of playing back the media data, wherein the client device includes a pre-decoder buffer for receiving the transmitted packets from the source server via the network, the pre-decoder buffer having a variable initial buffering time and a variable buffer size, a decoder for decoding the packets from the pre-decoder buffer and means for dynamically adapting the variable initial buffering time and the variable buffer size of the pre-decoder buffer for improved playback performance by the client device.
- a client device for receiving a plurality of data packets transmitted over a network from a source server, the client device including a pre-decoder buffer for receiving the transmitted data packets from the source server via the network, the pre-decoder buffer having a variable initial buffering time and a variable buffer size, a decoder for decoding the data packets from the pre-decoder buffer, and means for dynamically adapting the variable initial buffering time and the variable buffer size of the pre-decoder buffer for improved playback performance by the client device.
- a new buffering block is provided in the terminal architecture in order to provide improved receiver-side buffering.
- This buffering block is herein referred to as a pre-decoder buffer.
- FIG. 1 shows a simplified block diagram of a pre-decoder buffer block in the device terminal architecture, in accordance with an embodiment of the invention.
- the "Transport decoder” 100 decapsulates the code-stream from the received data packets (e.g. RTP data packets).
- the "Source decoder” 120 decodes the code-stream to an uncompressed data format that can be played back.
- the "Pre-decoder buffer” 110 operates as a temporary storage between transport decoding and source decoding. In the case of a multi-media data stream comprising more than one type of data, a common pre-decoder buffer is advantageously shared between all real-time media types that are transmitted.
- a separate pre-decoder buffer is provided for each media type, the pre-decoder buffer for each media type being located between the transport decoder and the respective source decoder for the media type in question.
- the decoding operations are preferably implemented as software stored in the memory of the client device and run by and under the control of a MCU (Master Control Unit) that controls the operation of the client device, of which Figure 1 shows a part.
- the MCU receives control signals from a source server and controls the adaptation of the initial buffering time and the buffer size according to the received signals from the source server.
- the control of the different blocks by the MCU is illustrated in Figure 1 by the control arrows from the MCU to each block.
- the pre-decoder buffer is provided in addition to a post-decoder buffer located after a decoder in a streaming client.
- the post-decoder buffer is provided in order to absorb network transmission delay variations.
- the post-decoder buffer can also absorb decoding-related delay variations. This is particularly advantageous in the case where more than one type of media data is streamed simultaneously. The use of a post-decoder buffer in this situation enables decoding delay variations introduced by different media decoders to be smoothed out.
- a separate decoder buffer is also provided in the receiving client.
- the decoder buffer is located between the decoder and the post-decoder buffer and is provided as a temporary store for media data as it is decoded.
- a separate decoder buffer is provided for the respective source decoder for each media type.
- a buffering algorithm operating in accordance with the embodiment is provided to buffer received data in a streaming client and to control the encoding and serving of streams from a network-based streaming server.
- the algorithm assumes that a pre-decoder buffer according to the invention is provided in the streaming client.
- the initial buffering time typically refers to the time that elapses between the time when a first media data packet is received and the time when the first media sample is played back.
- the minimum pre-decoder buffer size typically corresponds to the amount of data (e.g. the number of bytes of data) the streaming client is able to store in addition to the buffering that takes place to cope with the transmission delay variation. In other words, a minimum pre-decoder buffer size is defined for zero-delay reliable transmission networks.
- the buffering algorithm is similar to the algorithms described in H.263 Annex B (Hypothetical Reference Decoder) and MPEG-4 Visual Annex D (Video buffering verifier). These algorithms define the buffering behavior for video codecs. It should be noted that these algorithms cannot be used to replace the proposed pre-decoder buffering algorithms, because they are applicable to video only. Moreover, the H.263 Hypothetical Reference Decoder does not support initial buffering or storing of multiple (non-B) frames into the buffer. It should also be noted that the proposed pre-decoder buffering algorithm is fully compatible with the previously mentioned video buffering algorithms. In a practical implementation, the pre-decoder buffer and the video decoder buffer can be combined.
- the buffering algorithm constrains a transmitted data packet stream to comply with the requirements of the pre-decoder buffer which are defined as follows:
- client-side pre-decoder buffering is likely to be combined with network delay jitter buffering. Consequently, the actual pre-decoder buffer size in a streaming client is likely to be larger than the minimum pre-decoder buffer size discussed above, and the actual initial buffering time is also likely to be longer than the initial buffering time discussed above.
- Figure 2 shows an example of a data flow in a typical streaming system illustrating the effect of pre-decoder buffering.
- the bars represent media frames or packets, for example, the dark bars are video data packets (e.g. encoded according to ITU-T recommendation H.263) and the light bars are audio data packets (e.g. encoded using the Adaptive Multi-Rate (AMR) speech codec).
- the height of the bars represent the size of a frame (or a packet) in bytes.
- the processing flow runs from the top to the bottom, and time runs from left to right.
- the input data is encoded.
- the video stream has a varying frame rate and frame size
- the audio stream has a constant frame rate but a varying frame size.
- the compressed media streams are encapsulated into packets and transmitted to the network. While encapsulating, the server splits large video frames to multiple packets, and combines a number of small audio frames into one packet.
- the server transmits packets at regular intervals. A constant network transmission delay is assumed, regardless of the packet size or any other factors. Thus, the relative timing of received packets is the same as when they were sent.
- the received packets are stored in a pre-decoder buffer. After a certain initial buffering time, frames are retrieved from the buffer, and the frame removal rate is the same as the frame playback rate.
- the maximum buffer occupancy level determines the minimum pre-decoder buffer size.
- the buffer characteristics can be defined primarily by two factors i.e. the initial buffering time and the minimum pre-decoder buffer size.
- An example for the default value for the initial buffering time is approximately one second and the default minimum pre-decoder buffer size is about 30720 bytes. It should be noted that these values are only exemplary and they may be varied to achieve suitable performance for the particular type of delays experienced in the network at the time. The suggested default values are based on practical experiments in a generalized environment that are in no way specific but take into account the most commonly occurring packet transmission scenarios.
- the default pre-decoder initial buffering time and the default pre-decoder buffer size may be defined implicitly.
- the source server and streaming clients in the network operate in such a way that certain default pre-decoder buffer parameters (e.g. pre-decoder initial buffering time and / or pre-decoder buffer size) are assumed.
- explicit signaling of the pre-decoder buffer parameters is used.
- RTSP Real Time Streaming Protocol
- the client terminal device can request the server to set either one or both of the following parameters:
- the client terminal device is not permitted to signal parameter values smaller than the default values defined or implicitly assumed in the streaming system.
- a server that receives a request indicating a value smaller than one of the default values may signal a "Bad Request". If the transmitted values are greater than or equal to the defined or implicit default values, the signaled values are taken into use substantially immediately the request is received and the source server verifies the transmitted packet stream using the signaled values according to the previously described buffering algorithm. In other words, and as described in greater detail below, the server transmits the packet stream in such a way that it can be played back in a substantially correct manner at the receiving client.
- the source server transmits the packet stream so as to ensure that over-flow of the pre-decoder buffer in the-receiving client does not occur and that all data chunks (e.g. frames) of the media data are available for playback in the receiving client at their scheduled playback times.
- a client terminal device when a client terminal device first establishes communication with a network server and starts to set up a streaming session with the server by requesting certain media content to be streamed, it signals its default pre-decoder buffering parameters to the server.
- the client terminal device may either indicate its default pre-decoder buffering time or its minimum pre-decoder buffer size, or both the aforementioned parameters.
- the post-decoder buffer size may be indicated to the source server.
- pre-decoder buffer parameters are defined implicitly in the streaming system
- initial signaling of pre-decoder buffer parameters by the client device is strictly unnecessary.
- a particular client device has pre-decoder buffering capabilities superior to the implicitly defined default values assumed in the streaming system, it can signal those to the server.
- the source server retrieves the pre-decoder buffer parameters for a given client device from a capability server in connection with the streaming system.
- the server next indicates to the client terminal device the characteristics of the media streams it can provide.
- a streaming server is provided with a plurality of pre-encoded media streams representing the same media content.
- Each of the pre-encoded streams is encoded with different encoding parameters. This arrangement enables the media content to be streamed to a plurality different client terminal devices having different properties and / or capabilities and / or via networks having different characteristics (e.g. maximum available transmission bit-rate).
- the server once the server has received an indication of the client terminal's default pre-decoder initial buffering time and / or its minimum pre-decoder buffer size, it informs the client terminal, by means of signaling via the network, of the different pre-encoded media streams it can provide. For example, if the server has 4 differently encoded media streams relating to the requested media content and the client has indicated both its default pre-decoder initial buffering time and its default pre-decoder buffer size, the server signals the pre-decoder initial buffering time and pre-decoder buffer size required to ensure correct (e.g. pause-free) playback of the 4 different media streams.
- the client terminal selects one of the 4 pre-encoded media streams for playback and adjusts its pre-decoder initial buffering time and pre-decoder buffer size according to the corresponding requirements of the chosen media stream.
- the adjustment within the client terminal is preferably controlled by the MCU of the client terminal. If the server indicates only the required pre-decoder initial buffering time or the required pre-decoder buffer size required by the various encoded media streams, the client terminal selects the media stream on that basis and adjusts either its pre-decoder initial buffering time or pre-decoder buffer size accordingly. In this case, whichever parameter is not indicated is assigned a default value.
- the client terminal then signals its choice of media stream to the server so that streaming download of the media content can commence.
- This step also informs the server implicitly of the pre-decoder initial buffering time and / or pre-decoder buffer size now valid in the client terminal and enables the server to correctly verify the transmitted media stream according to the previously described buffering algorithm, so that overflow of the pre-decoder buffer does not occur and all data chunks of the media data are available for playback in the receiving client at their scheduled playback times.
- the method according to the invention enables the terminal to receive and correctly reproduce media streams encoded in such a way that they would not be capable of correct reproduction using the default pre-decoder buffer parameters.
- the pre-decoder initial buffering time and / or pre-decoder buffer size in the client are adapted according to the previously described process whenever streaming of a new media stream is initiated. If it is determined during the process that the new media stream can be played back correctly at the client using the currently valid pre-decoder buffering parameters, no adjustments are necessary. Additionally, the client may adjust its pre-decoder initial buffering time and / or pre-decoder buffer size in a situation where the server signals a change in required pre-decoder buffer parameters during an existing streaming session. This situation may arise, for example, if different consecutive sections of the media content to be streamed are encoded differently, giving rise to a need for different pre-decoder buffering at the client to ensure correct playback of the stream.
- the present invention contemplates a pre-decoder buffer as a part of a streaming client.
- the streaming client operates by following a buffering algorithm in which a streaming server verifies that the transmitted data stream complies with the defined buffering algorithm.
- the invention proposes mechanisms for defining and signaling the buffer capabilities of a streaming client to a streaming server. In this way a streaming server can obtain information about the buffering capabilities of a given streaming client and the encoded data/media transmission rate can be allowed to vary within the limits of the receiver-side pre-decoder buffer.
- a buffering verifier in a server can be used to ensure that the transmitted packet stream complies with the receiver buffering capabilities.
- the server may adjust the way in which media data is encoded and packetised.
- the buffering verifier can be a buffer running within the server after the transport encoder.
Abstract
Description
- The present invention relates generally to the streaming of media over packet-based networks. More specifically, the invention relates a buffering mechanism for improving playback of the streamed media from packet delay variation due to encoding and packetisation.
- In conversational packet-switched multimedia systems, e.g., in IP-based video conferencing systems, different types of media are normally carried in separate packets. Moreover, packets are typically carried on top of a best-effort network protocol that cannot guarantee a constant transmission delay, but rather the delay may vary from packet to packet. Consequently, packets having the same presentation (playback) time-stamp may not be received at the same time, and the reception interval of two packets may not be the same as their presentation interval (in terms of time). Thus, in order to maintain playback synchronization between different media types and to maintain the correct playback rate, a multimedia terminal typically buffers received data for a short period (e.g. less than half a second) in order to smooth out delay variation. Herein, this type of buffer is referred to as a delay jitter buffer. In conversational packet-switched multimedia systems buffering can take place before and / or after media data decoding.
- Delay jitter buffering is also applied in streaming systems. Due to the fact that streaming is a non-conversational application, the delay jitter buffer required may be considerably larger than in conversational applications. When a streaming player has established a connection to a server and requested a multimedia stream to be downloaded, the server begins to transmit the desired stream. The player typically does not start playing the stream back immediately, but rather it buffers the incoming data for a certain period, typically a few seconds. Herein, this type of buffering is referred to as initial buffering. Initial buffering provides the ability to smooth out transmission delay variations in a manner similar to that provided by delay jitter buffering in conversational applications. In addition, it may enable the use of link, transport, and/or application layer retransmissions of lost protocol data units (PDUs). Buffering allows the player to decode and play data from the buffer while allowing the possibility for lost PDUs to be retransmitted. If the buffering period is sufficiently long the retransmitted PDUs are received in time to be decoded and played at the scheduled moment.
- Initial buffering in streaming clients provides a further advantage that cannot be achieved in conversational systems: it allows the data rate of the media transmitted from the server to vary. In other words, media packets can be temporarily transmitted faster or slower than their playback rate, as long as the receiver buffer does not overflow or underflow. The fluctuation in the data rate may originate from two sources. The first source of fluctuation is due to the fact that the compression efficiency achievable in some media types, such as video, depends on the contents of the source data. Consequently, if a stable quality is desired, the bit-rate of the resulting compressed bit-stream varies. Typically, a stable audio-visual quality is subjectively more pleasing than a varying quality. Thus, initial buffering enables a more pleasing audio-visual quality to be achieved compared with a system without initial buffering, such as a video conferencing system.
- Considering the example of video data in more detail, different frames of a video sequence may be represented by very different amounts of data. This results from the use of predictive encoding techniques. Typically, video encoding standards define at least two types of frame. The principal frame types are INTRA or I-frames and INTER or P-frames. An INTRA frame is encoded on the basis of information contained within the image itself, while a P-frame is encoded with reference to at least one other frame, usually a frame occurring earlier in the video sequence. Due to the significant temporal redundancy between successive frames of a digital video sequence, it is possible to encode an INTER frame with a significantly smaller amount of data than that required to represent an INTRA frame. Thus, INTRA frames are used comparatively infrequently in an encoded video sequence.
- Typically an encoded sequence starts with an INTRA frame (as there is no previous frame available to be used as a reference in the construction of an INTER frame). INTRA frames may be inserted into the sequence periodically e.g. at regular intervals, in order to compensate for errors that may accumulate and propagate through a succession of predicted (INTER) frames. INTRA frames are also commonly used at scene cuts where the image content of consecutive frames changes so much that predictive coding does not provide effective data reduction. Thus, a typical encoded video stream generally starts with an INTRA coded frame and comprises a sequence of INTER frames interspersed with occasional INTRA frames, the amount of data required to represent an INTRA frame being several (e.g. 5 - 10) times greater than that required to represent an INTER coded frame. The amount of data required to represent each INTER frame also varies according to the level of similarity / difference with its reference frame and the amount of detail in the image.
- This means that the information required to reconstruct a predictively encoded video sequence is not equally distributed amongst the transmitted data packets. In other words, a larger number of data packets is required to carry the data related to an INTRA frame than is required to carry the data for an INTER frame. Furthermore, as the amount of data required to represent consecutive INTER frames also varies depending on image content, the number of data packets required to carry INTER frame data also varies.
- A second source of fluctuation occurs when packet losses in fixed IP networks occur in bursts. In order to avoid bursty errors and high peak bit- and packet-rates, well-designed streaming servers schedule the transmission of packets carefully and packets may not be sent precisely at the rate they are played back at the receiving end. Typically, network servers are implemented in such a way that they try to achieve a constant rate of packet transmission. A server may also adjust the rate of packet transmission in accordance with prevailing network conditions, reducing the packet transmission rate when the network becomes congested and increasing it if network conditions allow, for example. This typically occurs by adjusting the advertised window of the acknowledgement message sent in TCP (transmission control protocol).
- Considering this embedded property of network servers, and in connection with the previously described video encoding system, not only is the information required to reconstruct a predictively encoded video sequence unequally distributed between the transmitted data packets, but the data packets themselves may also be transmitted from the server at a varying rate. This means that a decoder in, for example, a receiving client terminal experiences a variable delay in receiving the information that it requires to construct consecutive frames in a video sequence even if the transmission delay through the network is constant. It should be noted that the term client terminal refers to any end-user electronic device such as handheld devices (PDAs), wireless terminals, as well as desktop and laptop computers and set top boxes. This variation in delay, which arises due to encoding, packetisation and packet transmission from a server can be termed an "encoding" or "server-specific" variation delay. It is independent of, or in addition to, delay jitter that arises due to variations in transmission time within the network.
- Hence, initial buffering enables the accommodation of fluctuations in transmitted data rate from the aforementioned disadvantages i.e. encoding or server-specific delay variation and network transmission related delay variation. Initial buffering helps to provide a more stable audio-visual quality and to avoid network congestion and packet losses.
- Initial buffering may also be performed after decoding of the received media data. This has the disadvantage that the dimensions of the buffer must be relatively large, as the buffering is performed on decoded data. The combined effect of encoding, server-specific and network transmission delay variations also tends to increase the initial buffering requirement.
- Furthermore, the encoding of media data and the way in which encoded data is encapsulated into packets and transmitted from a server causes a decoder in a receiving client terminal to experience a variable delay in receiving the information it requires to reconstruct the media data, even if the transmission delay through the network is constant. Thus, a post-decoder buffer does not provide a means of absorbing this form of delay variation prior to decoding.
- Document
US 6175871 B1 discloses a system for receiving streaming media over a network which uses a pre-decoder buffer with a variable buffer size whereby the variable buffer size is dynamically adapted in accordance with the dynamic transporting characteristics of the network. - According to a first aspect of the invention there is a method of streaming media data by transmitting a plurality of data packets over a network from a source server to a client device wherein the client device includes a decoder for decoding encoded packets. The method is characterised in that the client device further includes a pre-decoder buffer having a variable initial buffering time and a variable buffer size established for receiving the transmitted data from the source server prior to decoding in the decoder, and wherein the variable initial buffering time and variable buffer size of the pre-decoder buffer are dynamically adapted for improved playback performance by the client device.
- According to a second aspect of the invention there is provided a system for streaming media data by transmitting a plurality of data packets, the system including a source server hosting the media data, a network serving as a transmission medium for the data packets; and a client device capable of playing back the media data, wherein the client device includes a pre-decoder buffer for receiving the transmitted packets from the source server via the network, the pre-decoder buffer having a variable initial buffering time and a variable buffer size, a decoder for decoding the packets from the pre-decoder buffer and means for dynamically adapting the variable initial buffering time and the variable buffer size of the pre-decoder buffer for improved playback performance by the client device.
- According to a third aspect of the invention there is provided a client device for receiving a plurality of data packets transmitted over a network from a source server, the client device including a pre-decoder buffer for receiving the transmitted data packets from the source server via the network, the pre-decoder buffer having a variable initial buffering time and a variable buffer size, a decoder for decoding the data packets from the pre-decoder buffer, and means for dynamically adapting the variable initial buffering time and the variable buffer size of the pre-decoder buffer for improved playback performance by the client device.
- The invention, together with further objectives and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings in which:
-
Figure 1 shows a simplified block diagram of a pre-decoder buffer block in the device terminal architecture, in accordance with an embodiment of the invention; and -
Figure 2 shows an example of a data flow in a typical streaming system illustrating the effect of pre-decoder buffering. - According to the invention, a new buffering block is provided in the terminal architecture in order to provide improved receiver-side buffering. This buffering block is herein referred to as a pre-decoder buffer.
-
Figure 1 shows a simplified block diagram of a pre-decoder buffer block in the device terminal architecture, in accordance with an embodiment of the invention. The "Transport decoder" 100 decapsulates the code-stream from the received data packets (e.g. RTP data packets). The "Source decoder" 120 decodes the code-stream to an uncompressed data format that can be played back. The "Pre-decoder buffer" 110 operates as a temporary storage between transport decoding and source decoding. In the case of a multi-media data stream comprising more than one type of data, a common pre-decoder buffer is advantageously shared between all real-time media types that are transmitted. However, in alternative embodiments of the invention, a separate pre-decoder buffer is provided for each media type, the pre-decoder buffer for each media type being located between the transport decoder and the respective source decoder for the media type in question. The decoding operations are preferably implemented as software stored in the memory of the client device and run by and under the control of a MCU (Master Control Unit) that controls the operation of the client device, of whichFigure 1 shows a part. The MCU receives control signals from a source server and controls the adaptation of the initial buffering time and the buffer size according to the received signals from the source server. The control of the different blocks by the MCU is illustrated inFigure 1 by the control arrows from the MCU to each block. - In a preferred embodiment of the invention, the pre-decoder buffer is provided in addition to a post-decoder buffer located after a decoder in a streaming client. Advantageously, the post-decoder buffer is provided in order to absorb network transmission delay variations. Additionally, the post-decoder buffer can also absorb decoding-related delay variations. This is particularly advantageous in the case where more than one type of media data is streamed simultaneously. The use of a post-decoder buffer in this situation enables decoding delay variations introduced by different media decoders to be smoothed out. In an alternative embodiment of the invention, a separate decoder buffer is also provided in the receiving client. The decoder buffer is located between the decoder and the post-decoder buffer and is provided as a temporary store for media data as it is decoded. Advantageously, in a situation in which more than one type of media data is streamed simultaneously, a separate decoder buffer is provided for the respective source decoder for each media type.
- A buffering algorithm operating in accordance with the embodiment is provided to buffer received data in a streaming client and to control the encoding and serving of streams from a network-based streaming server. The algorithm assumes that a pre-decoder buffer according to the invention is provided in the streaming client.
- There are two primary factors that affect the behavior of the buffering algorithm i.e. the initial buffering time and the minimum pre-decoder buffer size. The initial buffering time typically refers to the time that elapses between the time when a first media data packet is received and the time when the first media sample is played back. The minimum pre-decoder buffer size typically corresponds to the amount of data (e.g. the number of bytes of data) the streaming client is able to store in addition to the buffering that takes place to cope with the transmission delay variation. In other words, a minimum pre-decoder buffer size is defined for zero-delay reliable transmission networks.
- The buffering algorithm is similar to the algorithms described in H.263 Annex B (Hypothetical Reference Decoder) and MPEG-4 Visual Annex D (Video buffering verifier). These algorithms define the buffering behavior for video codecs. It should be noted that these algorithms cannot be used to replace the proposed pre-decoder buffering algorithms, because they are applicable to video only. Moreover, the H.263 Hypothetical Reference Decoder does not support initial buffering or storing of multiple (non-B) frames into the buffer. It should also be noted that the proposed pre-decoder buffering algorithm is fully compatible with the previously mentioned video buffering algorithms. In a practical implementation, the pre-decoder buffer and the video decoder buffer can be combined.
- In accordance with the preferred embodiment of the invention, the buffering algorithm constrains a transmitted data packet stream to comply with the requirements of the pre-decoder buffer which are defined as follows:
- 1. The pre-decoder buffer is initially empty.
- 2. Each received data packet is added to the pre-decoder buffer substantially immediately it is received. All protocol headers at the transmission protocol level (e.g. RTP layer) or any lower layer are removed.
- 3. Data is not removed from the pre-decoder buffer during a period called the initial buffering time that is started when the first data packet is added to the buffer.
- 4. When the initial buffering time has expired, a playback timer is started.
- 5. A data chunk is removed from the pre-decoder buffer substantially immediately when the playback timer reaches the scheduled playback time for the data chunk in question.
- 6. When the data is carried over a zero-delay reliable transmission network, the occupancy level of the pre-decoder buffer is not permitted to exceed a certain level called the pre-decoder buffer size.
- It should be noted that the requirements above describe the operation without intermediate pause requests. Each new play request (after a pause, for example) will follow the same requirements.
- Furthermore, the requirements above are based on the assumption of having a zero-delay reliable transmission network. Thus, in a practical implementation, client-side pre-decoder buffering is likely to be combined with network delay jitter buffering. Consequently, the actual pre-decoder buffer size in a streaming client is likely to be larger than the minimum pre-decoder buffer size discussed above, and the actual initial buffering time is also likely to be longer than the initial buffering time discussed above.
-
Figure 2 shows an example of a data flow in a typical streaming system illustrating the effect of pre-decoder buffering. The bars represent media frames or packets, for example, the dark bars are video data packets (e.g. encoded according to ITU-T recommendation H.263) and the light bars are audio data packets (e.g. encoded using the Adaptive Multi-Rate (AMR) speech codec). The height of the bars represent the size of a frame (or a packet) in bytes. The processing flow runs from the top to the bottom, and time runs from left to right. - Now referring to
Figure 2 in more detail, at first, the input data is encoded. As a result, the video stream has a varying frame rate and frame size, and the audio stream has a constant frame rate but a varying frame size. Next the compressed media streams are encapsulated into packets and transmitted to the network. While encapsulating, the server splits large video frames to multiple packets, and combines a number of small audio frames into one packet. The server transmits packets at regular intervals. A constant network transmission delay is assumed, regardless of the packet size or any other factors. Thus, the relative timing of received packets is the same as when they were sent. The received packets are stored in a pre-decoder buffer. After a certain initial buffering time, frames are retrieved from the buffer, and the frame removal rate is the same as the frame playback rate. The maximum buffer occupancy level determines the minimum pre-decoder buffer size. - In order to ensure certain minimum buffering capabilities in streaming clients, certain default buffer characteristics are defined. As described earlier, the buffer characteristics can be defined primarily by two factors i.e. the initial buffering time and the minimum pre-decoder buffer size. An example for the default value for the initial buffering time is approximately one second and the default minimum pre-decoder buffer size is about 30720 bytes. It should be noted that these values are only exemplary and they may be varied to achieve suitable performance for the particular type of delays experienced in the network at the time. The suggested default values are based on practical experiments in a generalized environment that are in no way specific but take into account the most commonly occurring packet transmission scenarios. It should also be noted that in a given streaming system the default pre-decoder initial buffering time and the default pre-decoder buffer size may be defined implicitly. In other words, the source server and streaming clients in the network operate in such a way that certain default pre-decoder buffer parameters (e.g. pre-decoder initial buffering time and / or pre-decoder buffer size) are assumed. In alternative embodiments, explicit signaling of the pre-decoder buffer parameters is used.
- In order to allow a streaming client to signal its default pre-decoder buffering capabilities to a source server and to enable it to receive media streams requiring more demanding buffering capabilities than the default capabilities, signaling based on the SET_PARAMETER method of the Real Time Streaming Protocol (RTSP) is used in the invention.
- By way of example, the client terminal device can request the server to set either one or both of the following parameters:
- 1. initialBufferingTimeInMSec (initial buffering time in milliseconds)
- 2. preDecoderBufferSizeInBytes (minimum pre-decoder buffer size in bytes)
- The client terminal device is not permitted to signal parameter values smaller than the default values defined or implicitly assumed in the streaming system. A server that receives a request indicating a value smaller than one of the default values may signal a "Bad Request". If the transmitted values are greater than or equal to the defined or implicit default values, the signaled values are taken into use substantially immediately the request is received and the source server verifies the transmitted packet stream using the signaled values according to the previously described buffering algorithm. In other words, and as described in greater detail below, the server transmits the packet stream in such a way that it can be played back in a substantially correct manner at the receiving client. More specifically, the source server transmits the packet stream so as to ensure that over-flow of the pre-decoder buffer in the-receiving client does not occur and that all data chunks (e.g. frames) of the media data are available for playback in the receiving client at their scheduled playback times.
- According to an advantageous embodiment of the invention, when a client terminal device first establishes communication with a network server and starts to set up a streaming session with the server by requesting certain media content to be streamed, it signals its default pre-decoder buffering parameters to the server. As explained above, according to the invention, the client terminal device may either indicate its default pre-decoder buffering time or its minimum pre-decoder buffer size, or both the aforementioned parameters. In an alternative embodiment, in which the client terminal device is also provided with a post-decoder buffer, the post-decoder buffer size may be indicated to the source server. In embodiments of the invention in which the pre-decoder buffer parameters are defined implicitly in the streaming system, initial signaling of pre-decoder buffer parameters by the client device is strictly unnecessary. However, if a particular client device has pre-decoder buffering capabilities superior to the implicitly defined default values assumed in the streaming system, it can signal those to the server. In a further alternative arrangement, the source server retrieves the pre-decoder buffer parameters for a given client device from a capability server in connection with the streaming system.
- The server next indicates to the client terminal device the characteristics of the media streams it can provide. As is well known to those of ordinary skill in the art, in many practical streaming systems, a streaming server is provided with a plurality of pre-encoded media streams representing the same media content. Each of the pre-encoded streams is encoded with different encoding parameters. This arrangement enables the media content to be streamed to a plurality different client terminal devices having different properties and / or capabilities and / or via networks having different characteristics (e.g. maximum available transmission bit-rate).
- According to the advantageous embodiment of the invention, once the server has received an indication of the client terminal's default pre-decoder initial buffering time and / or its minimum pre-decoder buffer size, it informs the client terminal, by means of signaling via the network, of the different pre-encoded media streams it can provide. For example, if the server has 4 differently encoded media streams relating to the requested media content and the client has indicated both its default pre-decoder initial buffering time and its default pre-decoder buffer size, the server signals the pre-decoder initial buffering time and pre-decoder buffer size required to ensure correct (e.g. pause-free) playback of the 4 different media streams. The client terminal then selects one of the 4 pre-encoded media streams for playback and adjusts its pre-decoder initial buffering time and pre-decoder buffer size according to the corresponding requirements of the chosen media stream. The adjustment within the client terminal is preferably controlled by the MCU of the client terminal. If the server indicates only the required pre-decoder initial buffering time or the required pre-decoder buffer size required by the various encoded media streams, the client terminal selects the media stream on that basis and adjusts either its pre-decoder initial buffering time or pre-decoder buffer size accordingly. In this case, whichever parameter is not indicated is assigned a default value.
- The client terminal then signals its choice of media stream to the server so that streaming download of the media content can commence. This step also informs the server implicitly of the pre-decoder initial buffering time and / or pre-decoder buffer size now valid in the client terminal and enables the server to correctly verify the transmitted media stream according to the previously described buffering algorithm, so that overflow of the pre-decoder buffer does not occur and all data chunks of the media data are available for playback in the receiving client at their scheduled playback times.
- By enabling the client terminal to adjust its pre-decoder initial buffering time and / or pre-decoder buffer size, the method according to the invention enables the terminal to receive and correctly reproduce media streams encoded in such a way that they would not be capable of correct reproduction using the default pre-decoder buffer parameters.
- According to the preferred embodiment of the invention, the pre-decoder initial buffering time and / or pre-decoder buffer size in the client are adapted according to the previously described process whenever streaming of a new media stream is initiated. If it is determined during the process that the new media stream can be played back correctly at the client using the currently valid pre-decoder buffering parameters, no adjustments are necessary. Additionally, the client may adjust its pre-decoder initial buffering time and / or pre-decoder buffer size in a situation where the server signals a change in required pre-decoder buffer parameters during an existing streaming session. This situation may arise, for example, if different consecutive sections of the media content to be streamed are encoded differently, giving rise to a need for different pre-decoder buffering at the client to ensure correct playback of the stream.
- In summary, the present invention contemplates a pre-decoder buffer as a part of a streaming client. The streaming client operates by following a buffering algorithm in which a streaming server verifies that the transmitted data stream complies with the defined buffering algorithm. Additionally, the invention proposes mechanisms for defining and signaling the buffer capabilities of a streaming client to a streaming server. In this way a streaming server can obtain information about the buffering capabilities of a given streaming client and the encoded data/media transmission rate can be allowed to vary within the limits of the receiver-side pre-decoder buffer. It should be noted that a buffering verifier in a server can be used to ensure that the transmitted packet stream complies with the receiver buffering capabilities. This can be done, for example, by adjusting the transmission times of packets from the server so that the buffering capabilities of the client's pre-decoder buffer are not exceeded. Alternatively, the server may adjust the way in which media data is encoded and packetised. In practice, the buffering verifier can be a buffer running within the server after the transport encoder.
Claims (14)
- A client device for receiving media data, the media data being received at the client device as a data packet stream, characterized in that the client device comprises:a source decoder; characterised by:a master control unit for sending information indicative of a client's pre-decoder buffering parameters, the information indicative of at least one of a default pre-decoder initial buffering time and a minimum pre-decoder buffer size; receiving information indicative of a pre-decoder initial buffering time and a pre-decoder buffer size for the media data; anda pre-decoder buffer coupled to the source decoder for buffering the media data temporarily prior to decoding in the source decoder in accordance with a buffering algorithm, behaviour of the buffering algorithm being affected by the pre-decoder initial buffering time and the pre-decoder buffer size; anda post-decoder buffer coupled to the source decoder for buffering the media data after decoding.
- A client device according to claim 1, characterized in that the master control unit is configured to indicate a post-decoder buffer size to a source server.
- A client device according to claim 1, characterized in that the client device is arranged to adjust its pre-decoder initial buffering time responsive to a received indication of a required pre-decoder initial buffering time or pre-decoder buffer size.
- A client device according to claim 1, characterized in that the client device is arranged to:receive information indicative of a plurality of at least one of a pre-decoder initial buffering time and a pre-decoder buffer size required to provide correct play-back of a plurality of different pre-encoded media streams representative of the same media content;select one of the different pre-encoded media streams for playback at the client device; andadjust its pre-decoder initial buffering time and pre-decoder buffer size according to the requirements of the selected media stream.
- A client device according to claim 1, characterized in that the client device is arranged to adjust at least one of its pre-decoder initial buffering time and its pre-decoder buffer size responsive to a change in required pre-decoder buffer parameters received during a streaming session.
- A server for streaming media data, the server comprises:means for receiving information indicative of a client's pre-decoder buffering parameters, the information indicative of at least one of a default pre-decoder initial buffering time and a minimum pre-decoder buffer size;characterised by means for sending information indicative of a pre-decoder initial buffering time and a pre-decoder buffer size parameter for the media data; ; andmeans for adapting the transmision of a plurality of data packets as a data packet stream to verify that the data packet stream transmitted complies with a buffering algorithm, behaviour of the buffering algorithm being affected by the pre-decoder buffering parameters for the media data.
- A server according to claim 6, characterized in that the server is arranged to retrieve pre-decoder buffering capabilities for the client device from a capability server.
- A server according to claim 6, characterized in that the server is provided with a plurality of different pre-encoded media streams representative of the same media content, and is arranged to signal at least one of a pre-decoder initial buffering time and a pre-decoder buffer size required to ensure correct play-back of each available pre-encoded media stream.
- A server according to claim 6, characterized in that the server is arranged to adjust the transmission times of data packets in order to ensure that the transmitted data packet stream does not exceed the buffering capabilities of the pre-decoder buffer in the client.
- A server according to claim 6, characterized in that the server is arranged to adjust the way in which the media data is encoded and packetised in order to ensure that the transmitted data packet stream does not exceed the buffering capabilities of the pre-decoder buffer in the client.
- A method for buffering media data in a client device, the media data being received at the client device as a data packet stream, the client device comprising a pre-decoder buffer for buffering the media data temporarily before decoding, characterized in that the method comprises:sending information indicative of the client's pre-decoder buffering parameters, the information indicative of at least one of a default pre-decoder initial buffering time and a minimum pre-decoder buffer size;receiving information indicative of a pre-decoder initial buffering time and a pre-decoder buffer size for the media data;buffering the media data in the pre-decoder buffer of the client device in accordance with a buffering algorithm, behaviour of the buffering algorithm being affected by the pre-decoder initial buffering time and the pre-decoder buffer size.
- A method according to claim 11, characterized in that the method further comprises:indicating a post-decoder buffer size to a source server.
- A method according to claim 11, characterized in that the method further comprises:receiving information indicative of a plurality at least one of a pre-decoder initial buffering time and a pre-decoder buffer size required to provide correct play-back of a plurality of different pre-encoded media streams representative of the same media content;selecting one of the different pre-encoded media streams for playback at the client device; andadjusting the pre-decoder initial buffering time and pre-decoder buffer size of the pre-decoder buffer according to the requirements of the selected media stream.
- A method according to claim 11, characterized in that the client device adjusts at least one of its pre-decoder initial buffering time and its pre-decoder buffer size responsive to a change in required pre-decoder buffer parameters received during a streaming session.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI20010239A FI118830B (en) | 2001-02-08 | 2001-02-08 | Streaming playback |
EP05018669A EP1605347B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
EP02711897A EP1358542B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
Related Parent Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP02711897.5 Division | 2002-02-08 | ||
EP05018669 Previously-Filed-Application | 2002-02-08 | ||
EP05018669.1 Division | 2005-08-29 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP2159684A2 EP2159684A2 (en) | 2010-03-03 |
EP2159684A3 EP2159684A3 (en) | 2010-03-10 |
EP2159684B1 true EP2159684B1 (en) | 2013-05-22 |
Family
ID=8560281
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP09166588.5A Expired - Lifetime EP2159684B1 (en) | 2001-02-08 | 2002-02-08 | Playback of streamed media |
EP05018669A Expired - Lifetime EP1605347B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
EP02711897A Expired - Lifetime EP1358542B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
Family Applications After (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05018669A Expired - Lifetime EP1605347B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
EP02711897A Expired - Lifetime EP1358542B1 (en) | 2001-02-08 | 2002-02-08 | Method and system for buffering streamed data |
Country Status (18)
Country | Link |
---|---|
US (1) | US7421508B2 (en) |
EP (3) | EP2159684B1 (en) |
JP (2) | JP2004525556A (en) |
KR (1) | KR100629158B1 (en) |
CN (1) | CN100504757C (en) |
AT (2) | ATE310275T1 (en) |
AU (1) | AU2002231829B2 (en) |
BR (1) | BRPI0206630B1 (en) |
CA (1) | CA2435936C (en) |
DE (2) | DE60233177D1 (en) |
EE (1) | EE04862B1 (en) |
FI (1) | FI118830B (en) |
HU (1) | HUP0302621A3 (en) |
MX (1) | MXPA03007096A (en) |
RU (1) | RU2302032C2 (en) |
SG (1) | SG148844A1 (en) |
WO (1) | WO2002063461A1 (en) |
ZA (1) | ZA200306100B (en) |
Families Citing this family (101)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6307487B1 (en) | 1998-09-23 | 2001-10-23 | Digital Fountain, Inc. | Information additive code generator and decoder for communication systems |
US7068729B2 (en) | 2001-12-21 | 2006-06-27 | Digital Fountain, Inc. | Multi-stage code generator and decoder for communication systems |
AU2002353301A1 (en) * | 2001-11-21 | 2003-06-10 | Canon Kabushiki Kaisha | Method and device for determining at least one multimedia data encoding parameter |
JP2004015114A (en) * | 2002-06-03 | 2004-01-15 | Funai Electric Co Ltd | Digital broadcast recording device and digital broadcast system provided with the same |
US9240810B2 (en) | 2002-06-11 | 2016-01-19 | Digital Fountain, Inc. | Systems and processes for decoding chain reaction codes through inactivation |
WO2004008673A2 (en) * | 2002-07-16 | 2004-01-22 | Nokia Corporation | Method for enabling packet transfer delay compensation in multimedia streaming |
WO2004019521A1 (en) * | 2002-07-31 | 2004-03-04 | Sharp Kabushiki Kaisha | Data communication device, its intermittent communication method, program describing its method, and recording medium on which program is recorded |
KR101143282B1 (en) | 2002-10-05 | 2012-05-08 | 디지털 파운튼, 인크. | Systematic encoding and decoding of chain reaction codes |
MY134659A (en) * | 2002-11-06 | 2007-12-31 | Nokia Corp | Picture buffering for prediction references and display |
KR100926711B1 (en) | 2003-02-07 | 2009-11-17 | 엘지전자 주식회사 | How to send and receive multimedia data |
WO2004072764A2 (en) * | 2003-02-13 | 2004-08-26 | Nokia Corporation | Method for signaling client rate capacity in multimedia streaming |
CN100568964C (en) * | 2003-02-18 | 2009-12-09 | 诺基亚有限公司 | Picture decoding method |
CA2515354C (en) * | 2003-02-18 | 2013-08-06 | Nokia Corporation | A method for buffering media data in systems where decoding order is different from transmission order |
US7353284B2 (en) * | 2003-06-13 | 2008-04-01 | Apple Inc. | Synchronized transmission of audio and video data from a computer to a client via an interface |
KR100651566B1 (en) * | 2003-08-26 | 2006-11-28 | 삼성전자주식회사 | Multimedia Player Using Output Buffering in Mobile Terminal and Its Control Method |
CN100412832C (en) * | 2003-09-02 | 2008-08-20 | 竺红卫 | Non-homogeneous multi media flow transmission regulation method based on priority regulation |
US8582659B2 (en) * | 2003-09-07 | 2013-11-12 | Microsoft Corporation | Determining a decoding time stamp from buffer fullness |
US8345754B2 (en) * | 2003-09-07 | 2013-01-01 | Microsoft Corporation | Signaling buffer fullness |
EP1665539B1 (en) | 2003-10-06 | 2013-04-10 | Digital Fountain, Inc. | Soft-Decision Decoding of Multi-Stage Chain Reaction Codes |
KR101014233B1 (en) * | 2003-10-22 | 2011-02-14 | 엘지전자 주식회사 | Method for managing and playing additional audio file related interactive optical disc |
US20050201471A1 (en) * | 2004-02-13 | 2005-09-15 | Nokia Corporation | Picture decoding method |
US7296205B2 (en) * | 2004-02-18 | 2007-11-13 | Nokia Corporation | Data repair |
KR101145261B1 (en) * | 2004-02-27 | 2012-05-24 | 삼성전자주식회사 | Information storage medium containing multimedia data, reproducing method and apparatus thereof |
US7418651B2 (en) | 2004-05-07 | 2008-08-26 | Digital Fountain, Inc. | File download and streaming system |
US9219729B2 (en) * | 2004-05-19 | 2015-12-22 | Philip Drope | Multimedia network system with content importation, content exportation, and integrated content management |
US9124907B2 (en) * | 2004-10-04 | 2015-09-01 | Nokia Technologies Oy | Picture buffering method |
US7447978B2 (en) * | 2004-11-16 | 2008-11-04 | Nokia Corporation | Buffering packets of a media stream |
US8218439B2 (en) * | 2004-11-24 | 2012-07-10 | Sharp Laboratories Of America, Inc. | Method and apparatus for adaptive buffering |
US7536469B2 (en) * | 2004-12-10 | 2009-05-19 | Microsoft Corporation | System and process for controlling the coding bit rate of streaming media data employing a limited number of supported coding bit rates |
US7543073B2 (en) * | 2004-12-10 | 2009-06-02 | Microsoft Corporation | System and process for performing an exponentially weighted moving average on streaming data to establish a moving average bit rate |
US20060143678A1 (en) * | 2004-12-10 | 2006-06-29 | Microsoft Corporation | System and process for controlling the coding bit rate of streaming media data employing a linear quadratic control technique and leaky bucket model |
TWI401918B (en) * | 2005-02-03 | 2013-07-11 | Nokia Corp | A communication method for signaling buffer parameters indicative of receiver buffer architecture |
BRPI0610404A2 (en) * | 2005-04-07 | 2012-01-10 | Nokia Corp | method, system and device for storing media stream packets, wireless communication device, server, multipoint media broadcasting server / service, device for receiving packets having a transmission schedule and at least one transmission frame, signal associated with a media stream, computer program product |
US7613112B2 (en) * | 2005-06-28 | 2009-11-03 | Nokia Corporation | Optimizing playback startup time of bursty real-time streams |
US7864814B2 (en) * | 2005-11-07 | 2011-01-04 | Telefonaktiebolaget Lm Ericsson (Publ) | Control mechanism for adaptive play-out with state recovery |
US8788933B2 (en) * | 2005-12-01 | 2014-07-22 | Nokia Corporation | Time-shifted presentation of media streams |
WO2007095550A2 (en) * | 2006-02-13 | 2007-08-23 | Digital Fountain, Inc. | Streaming and buffering using variable fec overhead and protection periods |
US9270414B2 (en) | 2006-02-21 | 2016-02-23 | Digital Fountain, Inc. | Multiple-field based code generator and decoder for communications systems |
US7971129B2 (en) | 2006-05-10 | 2011-06-28 | Digital Fountain, Inc. | Code generator and decoder for communications systems operating using hybrid codes to allow for multiple efficient users of the communications systems |
AU2007249777A1 (en) * | 2006-05-11 | 2007-11-22 | Cfph, Llc | Methods and apparatus for electronic file use and management |
US9386064B2 (en) | 2006-06-09 | 2016-07-05 | Qualcomm Incorporated | Enhanced block-request streaming using URL templates and construction rules |
US9432433B2 (en) | 2006-06-09 | 2016-08-30 | Qualcomm Incorporated | Enhanced block-request streaming system using signaling or block creation |
US9380096B2 (en) | 2006-06-09 | 2016-06-28 | Qualcomm Incorporated | Enhanced block-request streaming system for handling low-latency streaming |
US9209934B2 (en) | 2006-06-09 | 2015-12-08 | Qualcomm Incorporated | Enhanced block-request streaming using cooperative parallel HTTP and forward error correction |
US9178535B2 (en) | 2006-06-09 | 2015-11-03 | Digital Fountain, Inc. | Dynamic stream interleaving and sub-stream based delivery |
US9419749B2 (en) | 2009-08-19 | 2016-08-16 | Qualcomm Incorporated | Methods and apparatus employing FEC codes with permanent inactivation of symbols for encoding and decoding processes |
FR2907990B1 (en) | 2006-10-27 | 2009-04-17 | Envivio France Entpr Uniperson | TIME-REAL ENCODER CONSTRAINED IN FLOW AND TIME, PROCESS, COMPUTER PROGRAM PRODUCT AND CORRESPONDING STORAGE MEDIUM. |
US7962637B2 (en) * | 2006-11-03 | 2011-06-14 | Apple Computer, Inc. | Dynamic adjustments of video streams |
US8069260B2 (en) * | 2007-01-12 | 2011-11-29 | Microsoft Corporation | Dynamic buffer settings for media playback |
US8914529B2 (en) * | 2007-01-22 | 2014-12-16 | Microsoft Corporation | Dynamically adapting media content streaming and playback parameters for existing streaming and playback conditions |
GB0705329D0 (en) | 2007-03-20 | 2007-04-25 | Skype Ltd | Method of transmitting data in a communication system |
US20100135194A1 (en) * | 2007-03-27 | 2010-06-03 | Mitsuhiro Kubota | Mobile communication system, network apparatus, and packet sequence control method |
US9148628B2 (en) * | 2007-08-16 | 2015-09-29 | Yahoo! Inc. | Intelligent media buffering based on input focus proximity |
CA2697764A1 (en) | 2007-09-12 | 2009-03-19 | Steve Chen | Generating and communicating source identification information to enable reliable communications |
WO2009047713A2 (en) * | 2007-10-11 | 2009-04-16 | Nxp B.V. | Method and system for controlling the admission of a storage means to a perpheral bus of a data reproduction system |
RU2447489C1 (en) * | 2008-02-20 | 2012-04-10 | ЭлДжи ЭЛЕКТРОНИКС ИНК. | Device and method to design data unit which includes buffer status report |
US8126048B2 (en) * | 2008-03-18 | 2012-02-28 | Seiko Epson Corporation | Recording streaming delta-encoded data |
US8139923B2 (en) * | 2008-03-19 | 2012-03-20 | Seiko Epson Corporation | Playback of recorded streaming delta-encoded data |
EP2129130A1 (en) * | 2008-05-26 | 2009-12-02 | THOMSON Licensing | Simplified transmission method of a flow of signals between a transmitter and an electronic device |
US8379083B1 (en) * | 2008-07-17 | 2013-02-19 | Sprint Communications Company L.P. | Simultaneous viewing and reliable recording of multimedia content over a network |
JP5135147B2 (en) | 2008-09-29 | 2013-01-30 | 富士フイルム株式会社 | Video file transmission server and operation control method thereof |
JP5077181B2 (en) * | 2008-10-14 | 2012-11-21 | ソニー株式会社 | Information receiving apparatus, information transmitting apparatus, and information communication system |
KR101019594B1 (en) | 2008-11-10 | 2011-03-07 | 주식회사 케이티 | system for adjusting buffering time of streaming service and method thereof |
US9281847B2 (en) | 2009-02-27 | 2016-03-08 | Qualcomm Incorporated | Mobile reception of digital video broadcasting—terrestrial services |
JP5278059B2 (en) * | 2009-03-13 | 2013-09-04 | ソニー株式会社 | Information processing apparatus and method, program, and information processing system |
US9357568B2 (en) * | 2009-06-16 | 2016-05-31 | Futurewei Technologies, Inc. | System and method for adapting an application source rate to a load condition |
US20100329355A1 (en) * | 2009-06-30 | 2010-12-30 | Nxp B.V | System and method for configurable packet streaming |
US9288010B2 (en) | 2009-08-19 | 2016-03-15 | Qualcomm Incorporated | Universal file delivery methods for providing unequal error protection and bundled file delivery services |
US9917874B2 (en) | 2009-09-22 | 2018-03-13 | Qualcomm Incorporated | Enhanced block-request streaming using block partitioning or request controls for improved client-side handling |
JP5482178B2 (en) * | 2009-12-16 | 2014-04-23 | ソニー株式会社 | Transmitting apparatus and method, and receiving apparatus and method |
CN102724705B (en) * | 2009-12-25 | 2015-04-29 | 华为技术有限公司 | Buffer status reporting method and apparatus thereof |
TWI400949B (en) * | 2010-04-06 | 2013-07-01 | Hon Hai Prec Ind Co Ltd | Media data playback device and replay method thereof |
US8301794B2 (en) * | 2010-04-16 | 2012-10-30 | Microsoft Corporation | Media content improved playback quality |
US8532804B2 (en) * | 2010-06-18 | 2013-09-10 | Microsoft Corporation | Predictive resampler scheduler algorithm |
US9485546B2 (en) | 2010-06-29 | 2016-11-01 | Qualcomm Incorporated | Signaling video samples for trick mode video representations |
US8918533B2 (en) | 2010-07-13 | 2014-12-23 | Qualcomm Incorporated | Video switching for streaming video data |
US9185439B2 (en) | 2010-07-15 | 2015-11-10 | Qualcomm Incorporated | Signaling data for multiplexing video components |
KR20120034550A (en) | 2010-07-20 | 2012-04-12 | 한국전자통신연구원 | Apparatus and method for providing streaming contents |
US9596447B2 (en) | 2010-07-21 | 2017-03-14 | Qualcomm Incorporated | Providing frame packing type information for video coding |
US9456015B2 (en) | 2010-08-10 | 2016-09-27 | Qualcomm Incorporated | Representation groups for network streaming of coded multimedia data |
US9467493B2 (en) | 2010-09-06 | 2016-10-11 | Electronics And Telecommunication Research Institute | Apparatus and method for providing streaming content |
KR101739272B1 (en) | 2011-01-18 | 2017-05-24 | 삼성전자주식회사 | Apparatus and method for storing and playing contents in multimedia streaming system |
US8958375B2 (en) | 2011-02-11 | 2015-02-17 | Qualcomm Incorporated | Framing for an improved radio link protocol including FEC |
US9270299B2 (en) | 2011-02-11 | 2016-02-23 | Qualcomm Incorporated | Encoding and decoding using elastic codes with flexible source block mapping |
KR20120108564A (en) * | 2011-03-24 | 2012-10-05 | 삼성전자주식회사 | Data processing system, and method of operating the same |
US9253233B2 (en) | 2011-08-31 | 2016-02-02 | Qualcomm Incorporated | Switch signaling methods providing improved switching between representations for adaptive HTTP streaming |
US9843844B2 (en) | 2011-10-05 | 2017-12-12 | Qualcomm Incorporated | Network streaming of media data |
GB2495928B (en) | 2011-10-25 | 2016-06-15 | Skype | Jitter buffer |
GB2495929B (en) | 2011-10-25 | 2014-09-03 | Skype | Jitter buffer |
GB2495927B (en) | 2011-10-25 | 2015-07-15 | Skype | Jitter buffer |
CA2855845A1 (en) | 2011-11-18 | 2013-05-23 | Sirius Xm Radio Inc. | Systems and methods for implementing cross-fading, interstitials and other effects downstream |
US9779736B2 (en) | 2011-11-18 | 2017-10-03 | Sirius Xm Radio Inc. | Systems and methods for implementing efficient cross-fading between compressed audio streams |
EP2608558A1 (en) * | 2011-12-22 | 2013-06-26 | Thomson Licensing | System and method for adaptive streaming in a multipath environment |
MX343807B (en) | 2012-03-06 | 2016-11-24 | Sirius Xm Radio Inc | Systems and methods for audio attribute mapping. |
US9294226B2 (en) | 2012-03-26 | 2016-03-22 | Qualcomm Incorporated | Universal object delivery and template-based file delivery |
CN103476062B (en) * | 2012-06-06 | 2015-05-27 | 华为技术有限公司 | Data flow scheduling method, equipment and system |
US9246970B2 (en) * | 2014-02-14 | 2016-01-26 | GM Global Technology Operations LLC | System and method for compensating for delay and jitter |
US10283091B2 (en) | 2014-10-13 | 2019-05-07 | Microsoft Technology Licensing, Llc | Buffer optimization |
KR102350504B1 (en) * | 2015-04-27 | 2022-01-14 | 삼성전자주식회사 | Apparatus and method for controlling downlink throughput in communication system |
WO2020048617A1 (en) | 2018-09-07 | 2020-03-12 | Telefonaktiebolaget Lm Ericsson (Publ) | Latency efficient streaming of video frames for machine vision over an ip network |
EP4038892B1 (en) | 2019-10-14 | 2024-03-06 | Google LLC | Methods, systems, and media for streaming video content using adaptive buffers |
Family Cites Families (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5014265A (en) | 1989-11-30 | 1991-05-07 | At&T Bell Laboratories | Method and apparatus for congestion control in a data network |
EP0562221B1 (en) | 1992-03-27 | 1997-10-15 | Alcatel | Video decoder |
JPH0652666A (en) * | 1992-07-31 | 1994-02-25 | Matsushita Electric Ind Co Ltd | Multi-media reproducing device |
US5363097A (en) * | 1992-09-14 | 1994-11-08 | Industrial Technology Research Institute | Direct sequential-bit variable length decoder |
EP2190207A1 (en) | 1994-10-21 | 2010-05-26 | AT&T Corporation | Method of video buffer verification |
US5913031A (en) * | 1994-12-02 | 1999-06-15 | U.S. Philips Corporation | Encoder system level buffer management |
US5606369A (en) * | 1994-12-28 | 1997-02-25 | U.S. Philips Corporation | Buffering for digital video signal encoders using joint bit-rate control |
JP3060877B2 (en) * | 1995-02-20 | 2000-07-10 | 日本ビクター株式会社 | Multimedia scenario playback device |
US5808607A (en) * | 1995-04-07 | 1998-09-15 | International Business Machines Corporation | Multi-node media server that provides video to a plurality of terminals from a single buffer when video requests are close in time |
JPH09186966A (en) | 1995-12-25 | 1997-07-15 | Texas Instr Inc <Ti> | Video reproduction method and reproduction system |
US5790792A (en) * | 1996-09-04 | 1998-08-04 | Radiant Systems, Inc. | Method and apparatus for transmitting multimedia data from and application logic server to interactive multimedia workstations |
US6011590A (en) * | 1997-01-03 | 2000-01-04 | Ncr Corporation | Method of transmitting compressed information to minimize buffer space |
US5892980A (en) | 1997-02-28 | 1999-04-06 | Comsys Communication And Signal Processing Ltd. | System for dynamically changing the length of transmit and receive sample buffers utilizing previous responding to an interrupt in a communications system |
JPH10285591A (en) | 1997-04-02 | 1998-10-23 | Hitachi Denshi Ltd | Method and device for video signal transmission |
US6175871B1 (en) * | 1997-10-01 | 2001-01-16 | 3Com Corporation | Method and apparatus for real time communication over packet networks |
US6301258B1 (en) | 1997-12-04 | 2001-10-09 | At&T Corp. | Low-latency buffering for packet telephony |
JP2000228669A (en) * | 1999-02-08 | 2000-08-15 | Hitachi Ltd | Stream data delivery method in stream delivery system |
US6792615B1 (en) * | 1999-05-19 | 2004-09-14 | New Horizons Telecasting, Inc. | Encapsulated, streaming media automation and distribution system |
DE60032458T2 (en) | 2000-04-14 | 2007-04-12 | Alcatel | Self-adapting dither buffer |
CA2312333A1 (en) * | 2000-06-21 | 2001-12-21 | Kimihiko E. Sato | Multimedia compression, coding and transmission method and apparatus |
JP4596693B2 (en) * | 2000-07-06 | 2010-12-08 | パナソニック株式会社 | Streaming method and system for executing the same |
US7310678B2 (en) * | 2000-07-28 | 2007-12-18 | Kasenna, Inc. | System, server, and method for variable bit rate multimedia streaming |
US6768499B2 (en) * | 2000-12-06 | 2004-07-27 | Microsoft Corporation | Methods and systems for processing media content |
US6823394B2 (en) * | 2000-12-12 | 2004-11-23 | Washington University | Method of resource-efficient and scalable streaming media distribution for asynchronous receivers |
US6842433B2 (en) * | 2001-04-24 | 2005-01-11 | Wideray Corporation | System and method for communicating information from a computerized distributor to portable computing devices |
-
2001
- 2001-02-08 FI FI20010239A patent/FI118830B/en not_active IP Right Cessation
-
2002
- 2002-02-08 WO PCT/FI2002/000093 patent/WO2002063461A1/en active IP Right Grant
- 2002-02-08 AU AU2002231829A patent/AU2002231829B2/en not_active Expired
- 2002-02-08 SG SG200505021-6A patent/SG148844A1/en unknown
- 2002-02-08 MX MXPA03007096A patent/MXPA03007096A/en active IP Right Grant
- 2002-02-08 CN CNB028047648A patent/CN100504757C/en not_active Expired - Lifetime
- 2002-02-08 RU RU2003127066/09A patent/RU2302032C2/en active
- 2002-02-08 AT AT02711897T patent/ATE310275T1/en not_active IP Right Cessation
- 2002-02-08 EP EP09166588.5A patent/EP2159684B1/en not_active Expired - Lifetime
- 2002-02-08 BR BRPI0206630A patent/BRPI0206630B1/en active IP Right Grant
- 2002-02-08 DE DE60233177T patent/DE60233177D1/en not_active Expired - Lifetime
- 2002-02-08 JP JP2002563340A patent/JP2004525556A/en not_active Withdrawn
- 2002-02-08 CA CA2435936A patent/CA2435936C/en not_active Expired - Lifetime
- 2002-02-08 EP EP05018669A patent/EP1605347B1/en not_active Expired - Lifetime
- 2002-02-08 AT AT05018669T patent/ATE438136T1/en not_active IP Right Cessation
- 2002-02-08 HU HU0302621A patent/HUP0302621A3/en unknown
- 2002-02-08 EE EEP200300316A patent/EE04862B1/en unknown
- 2002-02-08 EP EP02711897A patent/EP1358542B1/en not_active Expired - Lifetime
- 2002-02-08 US US10/071,326 patent/US7421508B2/en not_active Expired - Lifetime
- 2002-02-08 DE DE60207381T patent/DE60207381T2/en not_active Expired - Lifetime
- 2002-02-08 KR KR1020037009374A patent/KR100629158B1/en active IP Right Grant
-
2003
- 2003-08-07 ZA ZA200306100A patent/ZA200306100B/en unknown
-
2006
- 2006-09-27 JP JP2006263162A patent/JP4690280B2/en not_active Expired - Lifetime
Also Published As
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2159684B1 (en) | Playback of streamed media | |
AU2002231829A1 (en) | Method and system for buffering streamed data | |
US8218439B2 (en) | Method and apparatus for adaptive buffering | |
US7652994B2 (en) | Accelerated media coding for robust low-delay video streaming over time-varying and bandwidth limited channels | |
US5867230A (en) | System, device, and method for streaming a multimedia file encoded at a variable bitrate | |
US7644176B2 (en) | Devices and methods for minimizing start up delay in transmission of streaming media | |
EP1514378B1 (en) | Multimedia server with simple adaptation to dynamic network loss conditions | |
US20040057446A1 (en) | Method for enabling packet transfer delay compensation in multimedia streaming | |
EP2196033B1 (en) | Method for an early start of audio-video rendering | |
US7111058B1 (en) | Server and method for transmitting streaming media to client through a congested network | |
KR20030014709A (en) | Video error resilience | |
WO2015061083A1 (en) | Adapting a jitter buffer | |
KR20100068780A (en) | Method and apparatus for preventing overflow of the pre-decoder buffer in the streaming service | |
KR20050019880A (en) | Method for enabling packet transfer delay compensation in multimedia streaming |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AC | Divisional application: reference to earlier application |
Ref document number: 1358542 Country of ref document: EP Kind code of ref document: P Ref document number: 1605347 Country of ref document: EP Kind code of ref document: P |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
17P | Request for examination filed |
Effective date: 20100908 |
|
17Q | First examination report despatched |
Effective date: 20101021 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AC | Divisional application: reference to earlier application |
Ref document number: 1358542 Country of ref document: EP Kind code of ref document: P Ref document number: 1605347 Country of ref document: EP Kind code of ref document: P |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 613553 Country of ref document: AT Kind code of ref document: T Effective date: 20130615 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 60245022 Country of ref document: DE Effective date: 20130711 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK05 Ref document number: 613553 Country of ref document: AT Kind code of ref document: T Effective date: 20130522 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130902 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130823 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 Ref country code: SE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130923 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: VDEP Effective date: 20130522 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 Ref country code: BE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20140225 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 60245022 Country of ref document: DE Effective date: 20140225 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20140208 Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140228 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140228 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20141031 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: MM4A |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140228 Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20140208 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E Free format text: REGISTERED BETWEEN 20150910 AND 20150916 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R081 Ref document number: 60245022 Country of ref document: DE Owner name: NOKIA TECHNOLOGIES OY, FI Free format text: FORMER OWNER: NOKIA CORPORATION, ESPOO, FI Ref country code: DE Ref legal event code: R081 Ref document number: 60245022 Country of ref document: DE Owner name: NOKIA TECHNOLOGIES OY, FI Free format text: FORMER OWNER: NOKIA CORPORATION, 02610 ESPOO, FI |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20130522 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20210126 Year of fee payment: 20 Ref country code: GB Payment date: 20210127 Year of fee payment: 20 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: PE20 Expiry date: 20220207 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20220207 |